scott kirkpatrick Posted April 4, 2007 Share #1 Posted April 4, 2007 Advertisement (gone after registration) A thread with a boring title that has disappeared from the front page recently reported what seems to be a reasonable explanation for one case of SDS. http://www.leica-camera-user.com/digital-forum/20677-m8-replaced-now-what.html After the camera went back to Solms, he discovered one of his batteries, probably the last one to be used, was dead. Li-Ion batteries show a range of voltages. 4.15 to 4.2 Volts is typical of a freshly, fully charged battery. My charger brings them to 4.17 V. When the camera indicator shows one bar down (150 exposures in my test) the voltage was 3.85. When my camera was left on to discharge the battery, it shut off at 3.55 V. The battery that was found to be bad after jlc's camera died shows less than 2 V. I hope this piece of evidence has been communicated to Solms now, but at the time, it was not. How to measure your battery's voltage? Lay it on its back with contacts up and facing you. The voltage you want is between contacts 2 and 6, counting from left to right. To make a solid, safe contact, I find a mat knife (plastic handle, razor blade sticking out) works well. Voltmeters start at about $10 at RadioShack. Anyone else care to test? The shutoff voltage hasn't been reported to my knowledge. A battery outside this voltage range is suspect. It is not clear whether a bad battery causes the camera to fail, or the camera has caused the battery and itself to fail, in this case. scott Link to post Share on other sites More sharing options...
Advertisement Posted April 4, 2007 Posted April 4, 2007 Hi scott kirkpatrick, Take a look here Explanation for sudden death syndrome?. I'm sure you'll find what you were looking for!
Jack MacDonough Posted April 4, 2007 Share #2 Posted April 4, 2007 That's a good guess so far. I just got my M8 back from having a SDS and will use your test to avoid a relapse on my new battery Link to post Share on other sites More sharing options...
scott kirkpatrick Posted April 4, 2007 Author Share #3 Posted April 4, 2007 Sensible. Did you send battery and charger back with your SDS body, as it now seems is probably the right thing to do? scott Link to post Share on other sites More sharing options...
carstenw Posted April 4, 2007 Share #4 Posted April 4, 2007 It sounds promising, and the battery/charger seem likely culprits anyway, but what about the people who had two or more batteries, who couldn't revive their M8? Link to post Share on other sites More sharing options...
hiro Posted April 4, 2007 Share #5 Posted April 4, 2007 Is there an internal battery that runs the shoot count, date/time, etc. and keeps them counting when the main battery drains out as in a computer? I remember my old Mac failed to startup many years ago when a small battery inside died. As soon as I chaged it with a fresh one, voila! I'm not much of a help here but the thought just came up. Link to post Share on other sites More sharing options...
scott kirkpatrick Posted April 4, 2007 Author Share #6 Posted April 4, 2007 It sounds promising, and the battery/charger seem likely culprits anyway, but what about the people who had two or more batteries, who couldn't revive their M8? Curiously, jrc's case doesn't seem to involve the charger, but one of his batteries and the camera conspired to let supply voltages drop below a safe level, and the result was a state in which a reboot was not possible, even with a fresh battery. Presumably this would require firmware corruption, not just loss of data like the date and time. Sounds like firmware changes could help. I'm a little suspicious of my charger -- it seems to recharge a partly discharged battery awfully fast, so now i measure the voltage of my batteries after a day of use, then time the recharge to see what sort of curve I get. scott Link to post Share on other sites More sharing options...
elansprint72 Posted April 4, 2007 Share #7 Posted April 4, 2007 Advertisement (gone after registration) The answer? : Sudden death syndrome - SDS raising awareness of cardiac abnormalities which can lead to sudden death Link to post Share on other sites More sharing options...
colorflow Posted April 4, 2007 Share #8 Posted April 4, 2007 I have reported my problems with SDS at this forum "my sudden death m8 returning from solms without repair", and recently just posted the following in another thread: "There is a lot of talk on this forum about sudden death, pointing the finger to the battery. The worst the battery can do is short life and low voltage which any self-respecting programmer should be able to handle and safe-guard against. Most M8s will encounter faulty batteries in their lives and must be able to handle them. I maintain the fault is in the firmware which, under certain power conditions (probably related to faulty battery), gets wrapped around the axel and requires a cold start (by draining the internal battery) to recover. Since we have not heard any new sudden deaths for a while, perhaps Leica already fixed it in one of the new firmware releases?" Alan Link to post Share on other sites More sharing options...
scott kirkpatrick Posted April 5, 2007 Author Share #9 Posted April 5, 2007 I was working at home today and decided to monitor a discharge cycle on my M8, just leaving the camera switched on with the display running in "play" mode. I have two batteries. Battery #2 I discharged to shutdown a few days ago, and measured after shutdown. It showed 4.17 V fully charged, and 3.55 V after shutdown in the morning. Battery #1 (today) also started at 4.17 V but after shutdown, about six hours later, it reached 3.46 volts. The discharge curve versus time is shown below. I was doing something more interesting and failed to monitor the last hour carefully, so my last data point could have occurred even earlier, and represents a falling off the cliff, as is known to be the shape of the endpoint of this battery technology. Presumably this is the part of the discharge process where trouble can occur, and the camera might not catch it in time. The camera battery gauge went to one bar at around 3.72 V, so my recommendation would be to recharge your battery when it reaches one bar, not wait for zero. scott Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/20558-explanation-for-sudden-death-syndrome/?do=findComment&comment=220938'>More sharing options...
LJL Posted April 5, 2007 Share #10 Posted April 5, 2007 Scott, Thank you for your measurement efforts and suggested prognosis. I had been suggesting this very scenario in several threads long ago, and commented that it did appear to be a power issue with the M8 and sudden death. (I also think there were several power and power switch issues that were givng folks a lot of grief.) I agree with your suggestion of pulling the battery when it is down to one bar, rather than taking it to zero, as that last power drop, characteristic of LiIon batteries seems to be what may be causing the problems with the M8. The firmware is not catching the decreasing voltage fast enough to freeze the system in a stable configuration and then allowing shutdown. Once things get scrambled, it seems as though many bets are off. Some have been fortunate with the procedure of letting the camera's internal battery also drain for several days and then the system resets to default. Others have not been as fortunate, and the camera died. I believe several of these ideas have been communicated to Leica, but it remains to be seen if they are able to install the proper shutdowns in the firmware to prevent further camera deaths. They are tearing several cameras apart now to find the problem, based on other threads and conversations, but we may not know the outcome for a while. Seems like a prudent solution is to not let things drop below 1 bar on the meter. Not what one should expect to have to monitor, but one of those little, but important bugs that need to be worked out. LJ Link to post Share on other sites More sharing options...
geoffreyg Posted April 5, 2007 Share #11 Posted April 5, 2007 this all sounds pretty reasonable, and you have provided a pretty good "hands-on" fix if this is the case. Good work, guys. Geoff Link to post Share on other sites More sharing options...
Riley Posted April 5, 2007 Share #12 Posted April 5, 2007 wasn't there something about the camera being hot to touch too ? Link to post Share on other sites More sharing options...
Guest guy_mancuso Posted April 5, 2007 Share #13 Posted April 5, 2007 Got a PM this morning from Andreas that leica is posting a FAQ and my laundry list on there web site at noon today. Andreas will post the links and such but hopefully this area will be touched on in the FAQ's. He also mentioned that leica loves the forum members around here and all that they do. Good stuff guys and gals. Link to post Share on other sites More sharing options...
LJL Posted April 5, 2007 Share #14 Posted April 5, 2007 wasn't there something about the camera being hot to touch too ? Rob, In some cases, yes. This was what I was referring to about the power/power switch issue. In some cases, the power switch on the camera seemed to come off of a setting, and may have been causing some shorting or rapid drain of the battery. Not all cameras that got hot died, from what I had been reading, including my own. Other cameras never got hot, but just died right out of the box. When I sent my M8 back to Solms, I asked them to tighten/adjust the power switch, as I thought it had too much play in it and was easily moved off of a set stop. It came back with a much more smooth and snug operation of the switch, and it never slips out of a setting now. There are two separate issues, but both are related to the power supply for the M8. That still seems to have some bugs around it....be it faulty batteries, faulty charger, or firmware that does not recognize the stored power levels properly. Just my thinking on this. LJ Link to post Share on other sites More sharing options...
newyorkone Posted April 5, 2007 Share #15 Posted April 5, 2007 First M8 serial# 3107XXX worked great but then died when battery level was down to one bar. Could not be revived by inserting a freshly charged battery. Removing the bottom cover would give the warning and removing SD card would throw up the no SD card warning but nothing else would work. Nothing in either LCD and buttons didn't function. I agree with the thinking that this might be a firmware issue and that it probably isn't a hardware or quality control issue. Even if the firmware issue gets ironed out in the future I still think it would be beneficial for Leica to program and implement a hard reset/cold restart feature that mimics what people have been doing by allowing the camera to drain of power. Maybe a certain sequence of button presses so that it can't be tripped accidentally and also a warning message, Are you sure? just is case as well. This will be very useful and it sure beats Leica having to deal with perfectly fine M8's hardware wise that just need a little coaxing Link to post Share on other sites More sharing options...
fotografr Posted April 5, 2007 Share #16 Posted April 5, 2007 I agree with the thinking that this might be a firmware issue and that it probably isn't a hardware or quality control issue. See this thread. http://www.leica-camera-user.com/digital-forum/20933-sudden-death-answer.html Link to post Share on other sites More sharing options...
scott kirkpatrick Posted April 5, 2007 Author Share #17 Posted April 5, 2007 I agree with the thinking that this might be a firmware issue and that it probably isn't a hardware or quality control issue. Even if the firmware issue gets ironed out in the future I still think it would be beneficial for Leica to program and implement a hard reset/cold restart feature that mimics what people have been doing by allowing the camera to drain of power. Latest information (see the other current thread) is that some bad components also plays a role in the cameras that were (are?) affected, but firmware might be able to protect against the over-discharge. I certainly agree that a cold restart at "factory defaults" would be desirable. But note that firmware is supposed to be firm, not corruptable. That way it will permit the cold restart approach to get you out of trouble. If the firmware is modified in the course of this problem, so that it cannot be used for a fresh start, that is not a very good design approach and should also be changed. scott Link to post Share on other sites More sharing options...
LJL Posted April 5, 2007 Share #18 Posted April 5, 2007 Well, I will be among the first to say that I am glad that Leica has tracked this down, and that it may rule out some of my worrying theories about things. That they found a bad transistor is not a good thing, unless they are also able to isolate that entire batch. Hopefully it will mean few failures, and they should be random, but it still is worrisome if you happen to have a marginal transistor that you have no way of knowing about. The other part about the battery supposedly being able to behave as they say should be more comforting. I am still going to err on the side of caution and pull the thing at one bar juice remaining. Scott, I agree with you that firmware is supposed to be firm and not get scrambled, so there still is something that needs to be totally locked down there also, I think. I see this as good news that the cause of the problem may have been isolated. If Leica is able to make sure the materials are really meeting specs for them and not failing like this, going forward, I have a lot more confidence in getting another body or two as needed. LJ Link to post Share on other sites More sharing options...
colorflow Posted April 6, 2007 Share #19 Posted April 6, 2007 Latest information (see the other current thread) is that some bad components also plays a role in the cameras that were (are?) affected, but firmware might be able to protect against the over-discharge. I certainly agree that a cold restart at "factory defaults" would be desirable. But note that firmware is supposed to be firm, not corruptable. That way it will permit the cold restart approach to get you out of trouble. If the firmware is modified in the course of this problem, so that it cannot be used for a fresh start, that is not a very good design approach and should also be changed. scott I doubt if the firmware is being corrupted. As you said firmware is firm. I think there is a fault in the firmware logic, probably triggered by low battery voltage (which in turn may be triggered by the bad transistor as Leica says), that results in the power downs of the various functions getting out of sync. In any case, there is more than just the transistor problem, but a cold start should provide a fresh start and clear up the problem. Alan Link to post Share on other sites More sharing options...
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